Rigging a flexible rod
I would start with one bone for the whole rod (the bendy part anyways), and weight all the geometry to that bone.  Then...


Get into bone edit mode, select the bone.
Invoke the Subdivide command on that bone, for that rod, I'd subdivide it about 6-8 times.  But use your judgement.
Get into Pose Mode, and select all the bones.
Select the rod mesh, and get into weight paint mode.
Hit the "W" key, and select "Assign Automatic from Bones" from the popup menu.


Automatic weights for stuff like this usually works out pretty good.  I'd recommend b-bones subdivision to you, but if your exporting to a Game Engine, I'm not sure those would be supported.